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[on:]

http://www.space.com/19781-asteroid-2012-da14-flyby-webcasts.html

[Reply #1 on:]

what i can't understand is if someone like nasa or similar had seen this metereo approcing, or we are completely unaware of some dangerus-but-not-too-big meter

[Reply #2 on:]

what i can't understand is if someone like nasa or similar had seen this metereo approcing, or we are completely unaware of some dangerus-but-not-too-big meter

The latter is true. Spotting such 'small' objects at distance is often more a matter of luck then anything else.

Lefty

[Reply #3 on:]

I read the blast was estimated at 500 kt, at an altitude of 10-15 miles. That's huge! I'm surprised it didn't do more damage. Good thing it wasn't closer in.

[Reply #4 on:]

I read the blast was estimated at 500 kt, at an altitude of 10-15 miles. That's huge! I'm surprised it didn't do more damage. Good thing it wasn't closer in.

The angle of entry had a lot to do with it as it passed through the atmosphere for much longer then if it was falling at a more vertical angle where it might well have reached ground before breaking up.

Lefty

[Reply #5 on:]

more are coming

[Reply #6 on:]

more are coming

Always have been coming and always will be coming, it's just that human's clock rate is just not tuned to the universe's clock rate.

Lefty

[Reply #7 on:]

what i can't understand is if someone like nasa or similar had seen this metereo approcing, or we are completely unaware of some dangerus-but-not-too-big meter

How wide is the sky and beyond, out past the Moon orbit? How small is a 1km rock at 500,000km? Now how small is a less than 20m rock?
At relative speeds of asteroid and Earth you need to find the asteroid(s) and determine if/where any might hit the sky in enough time to give meaningful warning, more than just "Everybody duck!" which really means get your cameras out.

A 17m rock didn't get noticed until 32 seconds(?) before it exploded. Then it got noticed. That was the warning but who knew what to do? Maybe people knowing more what they see and take action to get under cover is sooner possible? That rock could have killed most everyone in the open for many km around just from the blast had it come much lower.

I think of these rocks and the ones going by as missed resources. I won't say they'd be used wisely (more likely be used to take war to a new level) but there they are.

[Reply #8 on:]

what i can't understand is if someone like nasa or similar had seen this metereo approcing, or we are completely unaware of some dangerus-but-not-too-big meter

How wide is the sky and beyond, out past the Moon orbit? How small is a 1km rock at 500,000km? Now how small is a less than 20m rock?
At relative speeds of asteroid and Earth you need to find the asteroid(s) and determine if/where any might hit the sky in enough time to give meaningful warning, more than just "Everybody duck!" which really means get your cameras out.

A 17m rock didn't get noticed until 32 seconds(?) before it exploded. Then it got noticed. That was the warning but who knew what to do? Maybe people knowing more what they see and take action to get under cover is sooner possible? That rock could have killed most everyone in the open for many km around just from the blast had it come much lower.

I think of these rocks and the ones going by as missed resources. I won't say they'd be used wisely (more likely be used to take war to a new level) but there they are.

wrong. the russian meteor was noticed and shot at by aliens protecting us. goto youtube and look it up

[Reply #9 on:]

I'll file that with "chem-trails"^TM and how real contrails don't last... not since WWII anyway.

[Reply #10 on:]

what i can't understand is if someone like nasa or similar had seen this metereo approcing, or we are completely unaware of some dangerus-but-not-too-big meter

How wide is the sky and beyond, out past the Moon orbit? How small is a 1km rock at 500,000km? Now how small is a less than 20m rock?
At relative speeds of asteroid and Earth you need to find the asteroid(s) and determine if/where any might hit the sky in enough time to give meaningful warning, more than just "Everybody duck!" which really means get your cameras out.

A 17m rock didn't get noticed until 32 seconds(?) before it exploded. Then it got noticed. That was the warning but who knew what to do? Maybe people knowing more what they see and take action to get under cover is sooner possible? That rock could have killed most everyone in the open for many km around just from the blast had it come much lower.

I think of these rocks and the ones going by as missed resources. I won't say they'd be used wisely (more likely be used to take war to a new level) but there they are.

i can understand Radar in space will not work, but maybe you can do something similar with light (see lidar)...
An easyer way should be something like automatic photo + redshift, or triangulation, analysis..
I've seen a "automatic pilot" for spaceship that autocorrect inertial measurement "simply" taking photo of the know star and calculating the error... like sailor
that can be used to track and identify any object into certain range

[Reply #11 on:]

i can understand Radar in space will not work,

Radar works just fine from earth to space. However the size of the return signature is related to both the distance and size of the object, so it's a sensitivity issue. The most sensitive method of detected far off and small space objects is photographs taken over multiple days looking at an identical part of space. Any object that has 'moved' relative to the background starts will appear as a streak and is easily to identify, track, and predict it's path thereafter. However there is a lot of space to look at and a finite number of picture takers so smaller objects are always subject to arriving without notice.

Lefty

[Reply #12 on:]

i can understand Radar in space will not work,

Radar works just fine from earth to space.

sorry, you are right, i get confused with Sonar

However the size of the return signature is related to both the distance and size of the object, so it's a sensitivity issue. The most sensitive method of detected far off and small space objects is photographs taken over multiple days looking at an identical part of space. Any object that has 'moved' relative to the background starts will appear as a streak and is easily to identify, track, and predict it's path thereafter. However there is a lot of space to look at and a finite number of picture takers so smaller objects are always subject to arriving without notice.
Lefty

ok, so it is similar to my precedent idea. It is just harder than i through

[Reply #13 on:]

yous are all wrong. nasa can track a wrench floating around. they kept this whole thing secret so to not create havoc in the streets!

Plus the sound of the meteor blast over Russia was detected from as far away as Antarctica by the far-flung system of detectors that make up the Comprehensive Nuclear-Test-Ban Treaty network. http://oak.ctx.ly/r/2h1l sorry bout the giant pic

[Reply #14 on:]

Radar is inverse square including the return, inverse-square of -less-. That limits the degrees a radar may scan very far, the size of the sky may be thought in terms of scan circles. The sky is much bigger than it looks, and it looks awful big.

TT:
They track 1,000's of junk objects in orbit. It's easier to do when you have satellites in place and you're only scanning local space. It's easier when you have decades to build the map.

The Vienna, Austria-based Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) runs the International Monitoring System made up of infrasound stations. Infrasound is low frequency sound with a range of less than 10 Hertz. Humans cannot hear the low frequency waves that were emitted by the meteor blast over Russia on Friday (Feb. 15), but they were recorded by the CTBTO’s network of sensors as they travelled across continents.

Gee, they caught it late. Not until the blast. Meanwhile phone and dash cams were already on the big glowing thundering thing blazing across the sky, and it ain't the Second Coming!